The phrase "a much slimmer" is correct and usable in written English.
It can be used when comparing the size or weight of something, indicating a significant reduction in size or weight.
Example: "After months of dieting and exercise, she is now a much slimmer version of her former self."
Alternatives: "a significantly thinner" or "a considerably leaner".
Breath is a much slimmer, rather conventionally structured novel.
They have a much slimmer chance of advancing to the title game with a victory.
Ironically, the magazine produced some of its best journalism in its last few months, albeit in a much slimmer package.
In the orange shirt and shorts of a Thai prison uniform, Bout cuts a much slimmer figure than before.
When he finally arrives half an hour late, it is a much slimmer version of the cricketing Flintoff.
Mr. Obama is also losing Florida and Virginia in this version of the model, and has a much slimmer lead, of about one percentage point, in Ohio.
Clarke is a much slimmed down version than the ample figure that held the claret jug aloft in 2011.
The implicit price deflator of the non-financial business sector (services as well as manufacturing) fell by 0.6% in the year to the second quarter the first fall since the second world war (see chart).The risk of deflation in the euro area as a whole remains much slimmer; inflation is still over 2%.
The Pixel 2 XL is supposed to be the bigger deal of the two new devices, in a few different ways: Unlike last year, Google will differentiate its larger-screened device with some improvements over the smaller, including a design with much slimmer bezels.
He was much slimmer; a letter to Onslow dated May 1875 reports a loss of 148 pound.
There is also a slim possibility -admittedly much slimmer - that the meeting in Iceland will lead to a breakthrough on strategic forces and defenses.
